Damselflies are a challenge, especially for a relative beginner like me. Young damsels emerge with soft bodies and weak wings, and are called tenerals. They're rather devoid of color and markings, so identification is difficult. The first 2 photos show a large tan teneral damselfy that we saw at Lake Lagunitas on Wednesday most likely a Vivid Dancer, with terminal appendages that suggest it might be a male. The young damsel flew weakly on glistening wings, moving 3-6' each time as if looking for a sunny spot in the dappled shade of the picnic area along the creek below Lake Lagunitas dam. Note how the 4 wings are held together above the abdomen, like a sail, a characteristic of the Dancers (Argia), wheres the Bluets (Enallagma) usuallt hold their folded wings lower, on one side or the other of the abdomen.
Teneral dragonflies are relatively devoid of color, but as the exoskeleton hardens color gradually appears, along with field marks that can make identification more positive. In the case of the Vivid Dancer the male will get a brilliant blue on the thorax and abdomen. Details on the thorax are also helpful and include a think black dorsal stripe and a humeral stripe on the side that thins out or disappears at its midpoint.
The female can be blue (andromorphic) or tan (gynomorphic), or other shades. The black markings are unique, with teardrop-shaped spots on the sides of the middle abdominal segments, as seen in this pair of Vivid Dancers in tandem position.
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